US3711762A - Polyphase transformer for a variable speed constant frequency system - Google Patents

Polyphase transformer for a variable speed constant frequency system Download PDF

Info

Publication number
US3711762A
US3711762A US00120156A US3711762DA US3711762A US 3711762 A US3711762 A US 3711762A US 00120156 A US00120156 A US 00120156A US 3711762D A US3711762D A US 3711762DA US 3711762 A US3711762 A US 3711762A
Authority
US
United States
Prior art keywords
transformer
core
teeth
phase
shells
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US00120156A
Other languages
English (en)
Inventor
R Eckenfelder
R Kautz
A Compoly
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bendix Corp
Original Assignee
Bendix Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bendix Corp filed Critical Bendix Corp
Application granted granted Critical
Publication of US3711762A publication Critical patent/US3711762A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F30/00—Fixed transformers not covered by group H01F19/00
    • H01F30/06—Fixed transformers not covered by group H01F19/00 characterised by the structure
    • H01F30/12—Two-phase, three-phase or polyphase transformers
    • H01F30/14—Two-phase, three-phase or polyphase transformers for changing the number of phases

Definitions

  • the number of teeth is a multiple of m, the number of phase voltages and of n the number of phase outputs. Wound on the teeth are m primary windings symmetrically arranged and each primary winding is energized by a phase voltage. 11 secondary windings are arranged on the core so that an output voltage is induced in each secondary winding and the secondary windings are positioned relative to one another in accordance with the desired phase angle separation of the outputs.
  • the invention relates to transformers and more particularly to polyphase transformers.
  • variable speed constant frequency systems used heretofor, in order to provide a three phase output by adding vectorially four three phase voltages separated in phase by four separate three phase transformers were used and the transformers were large, cumbersome and heavy and the assembly was difficult to mount.
  • the present invention overcomes this difficulty by using a single polyphase transformer which is relatively light in weight and simple to wind.
  • the four three phase voltages referred to in the example above comprise 12 voltages and the core includes 12 teeth.
  • a primary winding is wound on each tooth and each primary winding is energized by a phase voltage.
  • a secondary winding is provided on the core for each phase of the output and the secondary windings are arranged so that an output voltage is induced in each secondary winding and the secondary windings are positioned relative to one another in accordance with the phase angle separation of the outputs.
  • One object of the present invention is-to provide a polyphase transformer which may be used to combine any number of phase voltages and provide an output of 30 2 any desired phase of phases.
  • Another object is to provide a single polyphase transformer which is relatively small, light and easily mounted for combining a plurality of phase voltages.
  • FIG. 1 is a front view of a polyphase circular transformer constructed according to the invention and shows the arrangement of the primary and secondary windings on the core.
  • FIG. 2 shows the flux induced in the transformer core of FIG. 1 by energizing a single primary winding by one of the phase voltages.
  • FIG. 3 shows the arrangement of the secondary windings on the core in the second embodiment of the invention, the primary windings being arranged as shown in FIG. 1.
  • FIG. 4 is a perspective view of a third embodiment of the invention.
  • FIG. 5 is a top view of the embodiment shown in FIG. 4.
  • FIG. 1 a novel transformer constructed according to the invention is shown in FIG. 1 for combining twelve voltages forming the four three phase voltages described above.
  • the transformer comprises a circular laminated core 1 of magnetically permeable material with a central aperture 2.
  • Core 1 has a continuous outer shell 5 and a continuous inner shell 7 positioned concentrically and connected by twelve equally spaced teeth 9 disposed substantially radially therebetween and spaced 30 from one another.
  • Apertures 11 are formed in the core between the teeth.
  • a primary winding 13 is wound on each tooth 9 through the adjacent apertures 11 and has leads 15, 17 for connecting the primary winding to one of the phase voltages.
  • the transformer shown in FIG. 1 is designed to be energized by the 12 voltages.
  • the voltages may comprise four three phase voltages separated in phase by 15 and one phase voltage of each three phase voltage is applied to windings l3 identified in FIG. 1 as A-l, B- 1, C-1 and D-l.
  • a second phase voltage of each three phase voltage is applied to windings identified as A-2, 13-2, 02 and D-2 and the third voltage of each three phase voltage is applied to windings identified as A-3, 13-3, C-3 and 0-3.
  • the flux in the teeth does not vary by more than $20 percent and the flux in the outer shell and in the inner shell is a summation of the flux from all twelve teeth and is approximately twice the flux in one tooth so that for balanced flux density in the core the inner shell and outer shell cross sectional area should be about twice the cross sectional area of one tooth.
  • the flux in the shell is cyclic in nature and follows the input frequency. The flux pattern in the core from a single winding is quite complex and is approximated in FIG.
  • the distribution of the flux is determined by reluctances of the magnetic paths in the core.
  • the total flux due to one primary winding is:
  • Secondary winding 19 includes coils 25, 27 wound on outer shell 5 through apertures'll separated 120 from one another and the coils are connected by a lead 29. Secondary winding 19 has a neutral terminal N, connected to coil 27 and an output terminal connected to coil 25 for providing the X phase of the output. Secondary winding 21 includes coils 31, 33 wound on outer shell 5. Coil 31 is wound through the same aperture 11 as coil 25 and coil 33 is wound through an aperture 11 spaced 120 from coil 31 and the coils are connected by a lead 35.
  • Secondary winding 21 has a neutral terminal N connected to coil 31 and an output terminal (1),, connected to coil 33 for providing the Y phase.
  • Secondary winding 23 includes coils 37, 39 wound on outer shell 5. Coil 37 is wound through the same aperture 1 1 as coil 33 and coil 39 is wound through the same aperture 11 as coil 27 so that coils 37 and 39 are also spaced 120 from one another. The coils are connected by a lead 41.
  • Secondary winding 23 has a neutral terminal N, connected to coil 37 and an output terminal 1b, connected to coil 39 for providing the Z phase. Neutral terminals N,, N, and N are connected together when secondary windings 19, 21 and 23 are connected in Y configuration.
  • each secondary winding 43, 45 and 47 is wound on the core through apertures 11 separated by 120 and subtend the teeth and portions of the core therebetween.
  • coils 43 and 45 are wound through the same aperture and coils 45 and 47 are wound through the same aperture and coils 43 and 47 are wound through the same aperture as shown in FIG. 3.
  • Coil 43 has a neutral terminal N and an output terminal 4). for providing the X phase of the output.
  • Secondary winding 45 has a neutral terminal N and an output terminal for providing the Y phase of the output and secondary winding 47 has a neutral terminal N and an output terminal for providing the Z phase.
  • Neutral terminalsN N and N may be connected together when secondary windings 43, 45 and 47 are connected in Y configuration.
  • Secondary windings 43, 45 and47 provide a three phase output in which phases X, Y and Z are separated by 120.
  • the transformer shown therein has a triangular laminated core la of magnetically permeable material with a substantially central aperture 3a therein.
  • Core 1a is formed of an upper triangular shell 5a and a lower triangular shell 7a positioned parallel toone another and connected by 12 symmetrically arranged teeth 9a with apertures 11a between the teeth.
  • Each shell is assembledfrom a number of stampings and each shell comprises a triangular portion and onehalf each tooth 9a. Teeth 9a are bent at substantially right angles to the triangular portion and the ends of the teeth are machined. Two shells are assembled with the ends of adjacent teeth in engagement with one another and the shells are secured together by a bolt through aperture 3a.
  • a primary winding 13a is wound on each tooth 9a through adjacent apertures 11a and has leads 15a, 17a for connecting the primary winding to one of the phase voltages.
  • one phase voltage of each three phase voltage is applied to windings 13a identified in FIG. 4 as A-l, B-l, C-l.and D-l.
  • a second phase voltage of each three phase voltage is applied to windings identified as A-2, B-2, C-2 and 13-2 and the third phase voltage of each three phase voltage is applied to windings identified as A-3, B-3, C-3 and D3.
  • Secondary windings 19a, 21a and 23a are wound on the core through apertures 110 at the corners of the core and subtend the teeth and portions of the core therebetween similarly to theembodiment shown in FIG. 3.
  • the transformer shown in FIG. 4 operates in the same manner as the transformers shown in FIGS. 1
  • output power for each phase is derived in part from all 12 input phases so that power factor loading is no great problem to anyone input phase.
  • the inherent filtering ability of polyphase iron cores and vector summation of the 12 phase input voltages produces an output voltage with little harmonic content.
  • Square wave inputs across the primary windings produce sine wave output voltages in the secondary windings with no additional filtering.
  • the primary windings preferably are symmetrically distributed on the core and the secondary windings are arranged on the core relative to one another in accordance with the phase angle separation of the outputs.
  • the number of teeth should be equal to or a multiple of m, the number of input voltages and a multiple of n the number of phase outputs.
  • This arrangement permits m symmetrically distributed primary windings to be wound on the teeth of the core for energization by the input voltages and permits n secondary windings to be positioned relative to one another on the core to subtend a number of teeth corresponding to the desired phase angle separation of the outputs.
  • a transformer as described in claim 1 in which the number of teeth equal m the number of phase voltages and a primary winding is wound on each tooth.
  • a transformer of the kind described in claim 1 in which the shells are continuous and magnetic flux is induced in the shells by energization of the primary windings by the phase voltages.
  • a transformer of the kind described in claim 7 in which the shell cross sectional area is substantially twice the cross sectional area of a tooth so that the flux density is balanced.
  • a transformer as described in claim 2 in which the secondary windings are wound on the core about one of the shells and are arranged in accordance with the phase separation of the outputs.
  • a transformer as described in claim 5 in which the core is circular and the secondary windings are wound about one of the shells through the apertures and the windings are arranged on the core in accordance with the phase angle separation of the outputs.
  • a transformer as described in claim 5 in which the core is circular and each secondary winding is wound on the core through two apertures angularly spaced from one another in accordance with the angular phase separation of the outputs and subtend the teeth therebetween.
  • a transformer as described in claim 5 in which the core is triangular and each secondary winding is wound on the core through two apertures angularly spaced from one another in accordance with the angular phase separation of the outputs and subtend the teeth therebetween.

Landscapes

  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Coils Of Transformers For General Uses (AREA)
US00120156A 1971-03-02 1971-03-02 Polyphase transformer for a variable speed constant frequency system Expired - Lifetime US3711762A (en)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US12015671A 1971-03-02 1971-03-02

Publications (1)

Publication Number Publication Date
US3711762A true US3711762A (en) 1973-01-16

Family

ID=22388590

Family Applications (1)

Application Number Title Priority Date Filing Date
US00120156A Expired - Lifetime US3711762A (en) 1971-03-02 1971-03-02 Polyphase transformer for a variable speed constant frequency system

Country Status (7)

Country Link
US (1) US3711762A (ja)
JP (1) JPS553804B1 (ja)
CA (1) CA927489A (ja)
DE (1) DE2206610A1 (ja)
FR (1) FR2128336B1 (ja)
GB (1) GB1332084A (ja)
IT (1) IT949773B (ja)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4912618A (en) * 1988-11-04 1990-03-27 Sundstrand Corporation Variable speed, constant frequency generating system with input transformer
US5070441A (en) * 1990-12-24 1991-12-03 Ashley James R Distribution of power from a six phase powerline to one- and three- phase loads
US5317299A (en) * 1991-07-03 1994-05-31 Sundstrand Corporation Electromagnetic transformer
US5619407A (en) * 1996-02-06 1997-04-08 Robicon Corporation Autotransformer
AU2004227000B2 (en) * 1994-01-06 2007-10-11 Hyun Laboratory Co., Ltd. Power generator
US20090058584A1 (en) * 2007-08-29 2009-03-05 Siemens Energy & Automation, Inc. Three-phase multi-winding device

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3142269A1 (de) * 1981-10-24 1983-05-05 Thyssen Industrie Ag, 4300 Essen Stelltransformator
DE29503048U1 (de) * 1995-02-23 1995-04-13 Krafft, Michael, 59759 Arnsberg Drehstromtransformator
GB2458457B (en) * 2008-03-17 2010-10-20 Dynamic Dinosaurs Bv Transformer

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2471411A (en) * 1943-09-17 1949-05-31 Claesson Per Harry Elias Reactor
US2790131A (en) * 1955-04-25 1957-04-23 Nyyssonen Einard Polyphase transformer system
US2790130A (en) * 1953-11-10 1957-04-23 Nyyssonen Einard Polyphase transformer phase converter system
US3118070A (en) * 1959-08-18 1964-01-14 Bell Telephone Labor Inc Electrical control circuits
US3195081A (en) * 1963-11-04 1965-07-13 Westinghouse Electric Corp Electrical transformer having doublyoriented and random-oriented laminations

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3477010A (en) * 1967-04-11 1969-11-04 Lear Jet Ind Inc Synthetic wave three phase alternating current power supply system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2471411A (en) * 1943-09-17 1949-05-31 Claesson Per Harry Elias Reactor
US2790130A (en) * 1953-11-10 1957-04-23 Nyyssonen Einard Polyphase transformer phase converter system
US2790131A (en) * 1955-04-25 1957-04-23 Nyyssonen Einard Polyphase transformer system
US3118070A (en) * 1959-08-18 1964-01-14 Bell Telephone Labor Inc Electrical control circuits
US3195081A (en) * 1963-11-04 1965-07-13 Westinghouse Electric Corp Electrical transformer having doublyoriented and random-oriented laminations

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4912618A (en) * 1988-11-04 1990-03-27 Sundstrand Corporation Variable speed, constant frequency generating system with input transformer
US5070441A (en) * 1990-12-24 1991-12-03 Ashley James R Distribution of power from a six phase powerline to one- and three- phase loads
US5317299A (en) * 1991-07-03 1994-05-31 Sundstrand Corporation Electromagnetic transformer
AU2004227000B2 (en) * 1994-01-06 2007-10-11 Hyun Laboratory Co., Ltd. Power generator
AU2004227000C1 (en) * 1994-01-06 2008-04-17 Hyun Laboratory Co., Ltd. Power generator
US5619407A (en) * 1996-02-06 1997-04-08 Robicon Corporation Autotransformer
US20090058584A1 (en) * 2007-08-29 2009-03-05 Siemens Energy & Automation, Inc. Three-phase multi-winding device
US7948340B2 (en) * 2007-08-29 2011-05-24 Siemens Industry, Inc. Three-phase multi-winding device

Also Published As

Publication number Publication date
FR2128336B1 (ja) 1975-10-24
IT949773B (it) 1973-06-11
DE2206610A1 (de) 1972-09-21
CA927489A (en) 1973-05-29
GB1332084A (en) 1973-10-03
JPS553804B1 (ja) 1980-01-26
FR2128336A1 (ja) 1972-10-20

Similar Documents

Publication Publication Date Title
US11270831B2 (en) Three-phase reactor comprising iron-core units and coils
US4507635A (en) Magnetic anchoring apparatus with quadrangular pole arrangement
US3711762A (en) Polyphase transformer for a variable speed constant frequency system
US5654602A (en) Generator winding
US5801610A (en) Phase shifting transformer with low zero phase sequence impedance
US3665356A (en) Differential transformer with balancing means
US5317299A (en) Electromagnetic transformer
US3231841A (en) Combined transformer and choke unit
KR840006547A (ko) 정류기용 변압기
US6909352B2 (en) Endless core for a multiphase transformer and a transformer incorporating same
US3098990A (en) Precision voltage ratio transformer
US4689592A (en) Combined transformer and inductor
US3413580A (en) Multi-component electromagnet
US5565835A (en) Substantial nullification of external magnetic fields and lorentz forces regarding toroidal inductors
US4500829A (en) Advance and retard phase-shift transformer
US4112403A (en) Saturated reactor arrangements
US4491819A (en) Magnetically biased inductor
ZA200103849B (en) Endless core for a multiphase transformer and a transformer incorporating same.
US3732514A (en) Transformers
CN213660168U (zh) 一种分数匝变压器及其磁芯
US3436692A (en) Saturable reactor construction
US3478291A (en) Magnetic core and coil arrangement
WO2000030130A1 (en) Endless core for a multiphase transformer and a transformer incorporating same
US3358165A (en) Three-phase electric motors
US4185217A (en) Three pole electric motor